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Regarding terms in eigenfrequency equation

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Dear sir,

I am using eigenfrequency analysis of Solid Mechanics module for my micro-damper (COMSOL Multiphysics version 4.1). The solver executes the equation which is written in attached file (I was unable to type the same equation here so it is attached as docx file).

In this equation, F and v stands for what, I do not know.
Kindly let me know.

Thank you.
Best regards,
Rajeev Kumar Singh


1 Reply Last Post May 30, 2011, 2:22 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago May 30, 2011, 2:22 a.m. EDT
Hi

first I believe you are missing the "u" (in bold, as it's a vector, the dependent variables solved for in structural), and I believe it's a vector "Fv" and not a "dot product".

Second to show equations here on the forum, you can also use "snipp-it" or a similar tool to upload them as ".png" or ".jpg" files.

Then I propose that you take a look at the theory, it has come back again in the doc v4.1, even more in details with all the new structural goodies in V4.2. You can also turn on the equation view to understand what COMSOL is doing on it's internal

the Vector F are the generally the "external" force/flux applied on the system. Do not forget that the formulas shown by COMSOL are those applied to the infinitesimal dx*dy*dz element volume, hence to get to our usual units these must be integrated over the domains.

--
Good luck
Ivar
Hi first I believe you are missing the "u" (in bold, as it's a vector, the dependent variables solved for in structural), and I believe it's a vector "Fv" and not a "dot product". Second to show equations here on the forum, you can also use "snipp-it" or a similar tool to upload them as ".png" or ".jpg" files. Then I propose that you take a look at the theory, it has come back again in the doc v4.1, even more in details with all the new structural goodies in V4.2. You can also turn on the equation view to understand what COMSOL is doing on it's internal the Vector F are the generally the "external" force/flux applied on the system. Do not forget that the formulas shown by COMSOL are those applied to the infinitesimal dx*dy*dz element volume, hence to get to our usual units these must be integrated over the domains. -- Good luck Ivar

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